I have a project I am working on that uses an old portable CD player. I want the device to run off wall power but the port for the DC Adapter must need a proprietary tip to fit in the hole. I have tried the multi-tip DC adapters with the adjustable voltage but non of the tips fit. The player I have torn apart calls for 4.5v DC In. Can I work around the weird fitting for the tip?

Well it might take a bit of soldering to add a new power lead - bring it out through the hole where theold power socket was and use an inline DC power socket (one of the more common sizes like 2.1mmwould be a good choice).

Be sure to note the polarity and that the adapter is really generating 4.5V with enough current.

[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

I have a project I am working on that uses an old portable CD player. I want the device to run off wall power but the port for the DC Adapter must need a proprietary tip to fit in the hole. I have tried the multi-tip DC adapters with the adjustable voltage but non of the tips fit. The player I have torn apart calls for 4.5v DC In. Can I work around the weird fitting for the tip?

If it has a regular round plug then I seriously doubt it is a proprietary size, more than likely your adapter just doesn't have the right size. With that said, if you open it up you can easily solder right to the same terminals the plug is soldered to. You can also install your own plug.

It is a round plug. It is a Sony brand CD player. I looked on eBay for used Sony adapters. Some say 500mA and some say 400mA. Most of the listings say the tip is positive. I guess I could buy another multi-tip adapter and hope I find a tip that fits. The one I had before was either too loose or wouldn't fit over the center pin.

One other question. I do have a PSP power adapter and the tip fits in the CD player. However the PSP adapter says it outputs 5v. Is the difference between 4.5v and 5v enough to do serious damage to the player if I plug the PSP adapter in briefly to see if it will at least power on?

I ran into this on an Energizer external battery pack. The plug ended up having a 4.7mm outer diameter (and 2.1mm inner diameter) instead of the typical 5.0mm. You might want to get a caliper out and see if you can measure it. Small parts suppliers could probably get you one.